1. Field of the Invention
The invention relates to a maintenance apparatus for a medical or dental handpiece, and more particularly it concerns a novel apparatus for selectively supplying a maintenance medium to medical or dental handpieces which are mounted therein.
2. Description of the Related Art
Medical or dental handpieces are tube-like parts, which the doctor grasps during the treatment as grip sleeve. A typical such handpiece is a so-called drill handpiece, which carries the treatment tool at its forward end, e.g. a drill, and can be coupled with its rearward end with a connection part by means of a so-called plug-in/rotatable coupling, through which connection part supply lines for energy for driving the treatment instrument and also fluid lines for treatment media extend, which penetrate the plug-in/rotatable coupling and continue in the handpiece. The fluid lines may be lines carrying air, water or spray, which extend as channels or hose lines up to the forward end of the handpiece and emerge there, directed towards the treatment site. With a so-called turbine handpiece there is provided a compressed air line for supplying the turbine arranged in the forward end region of the handpiece, in a so-called drive channel, which compressed air line likewise penetrates the plug-in/rotatable coupling and extends to the turbine. So-called motor handpieces, which are driven by means of an electric motor, which is arranged in the above-mentioned connection part, likewise have a so-called drive channel, in which a drive shaft section is rotatably mounted, which extends to a spindle carrying the tool, in order to drive this spindle.
In functional operation of the above-mentioned handpieces maintenance is required from time to time, in particular of the drive channel and the drive elements rotatably mounted therein. Here it is to be taken into account that the handpieces, both in the case of motor drive and also turbine drive, may have drive elements rotating at high speed, which in the event of inadequate maintenance are particularly sensitive and rapidly wear, as a result of which repairs are needed.
With a known maintenance apparatus, described in DE 42 35 699 A1, for the maintenance of medical or dental handpieces, there is provided a water bath in which the handpiece is heated and cleaned by means of blowing through cold and/or hot compressed air, and thereafter can be maintained by blowing through a maintenance medium. Several handpieces can be subject to maintenance at the same time, which are held in a hanging or standing arrangement in each case at a connection part on a common carrier, which can be placed from above into a container holding the water bath. With this known maintenance apparatus, the handpieces are manually introduced from above into the container, in a vertical disposition, and connected with the connection parts.
For connecting the carrier with a supply line for a maintenance medium and a supply line for compressed air there is provided a line coupling which is located outside of the container and in the region of which a mechanical non-return valve is so arranged in each of these two lines that upon decoupling the valve body in each case self-actingly closes the fixed parts and line section.
A maintenance apparatus of the kind indicated in the introduction is described in EP 0 300 945 B1. This known maintenance apparatus has a housing enclosing a maintenance chamber which is accessible through a trapdoor having a pivot axis running at its lower edge. A plurality of connection pins for handpieces are provided, which handpieces can be plugged from below onto the connection pins, arranged in the upper region of the receiving chamber. Further, with this known maintenance apparatus, a safety valve is provided which closes the outlet from the connection pin on which no handpiece is placed. For the control of respective through-flows for a water mist and a disinfection mist to the connection parts, a control device is provided with associated electric valves.
With both above-described known maintenance apparatuses the supply of the maintenance medium to the connection parts is effected simultaneously. Here, significant differences between the quantities of maintenance medium supplied can occur between the connection parts, since a flow takes place more where it is subject to the least resistance. Different flow resistances can, however, scarcely be avoided in the region of the supply line branches. Furthermore, in particular different handpieces present the flow of maintenance medium with different flow resistances.
The object of the invention is, with a maintenance apparatus of the kind mentioned in the introduction, to ensure a sufficient supply of maintenance medium for each handpiece or to improve the supply and in particular to make more uniform the supply of maintenance medium.
This object is achieved by means of the structural arrangements described below.
With the maintenance apparatus in accordance with the invention the maintenance medium is supplied to the connection parts one after another, so that the supply to each occupied connection part is effected individually and thus the supplied quantity of maintenance medium can be made on the one hand in a controlled manner and on the other hand with slight quantity differences. With the configuration in accordance with the invention, the maintenance is thus significantly improved and there is effected in particular a reliable maintenance.
The configuration in accordance with the invention is admirably suitable for maintenance medium containers in the form of spray cans which are closed except for their outlet opening and which stand under self-pressure, whereby the issue of the maintenance medium is based on the action of a driver gas, which may be for example butane or isobutane or propane. The configuration in accordance with the invention leads also to a significant simplification, since such spray cans containing maintenance medium are available on the market and thus the maintenance apparatus does not need a special maintenance medium container but rather a conventional spray can, which due to its self-pressure requires no further feed drive for the flow of the maintenance medium. Since the supply capacity of a spray can is restricted due to the driver gas function, the configuration in accordance with the invention is particularly well suited for a spray can, because its capacity is excellently suited for the individual maintenance of the handpieces.
The latter advantages are also achieved by means of the configuration in accordance with the invention according to which the maintenance apparatus has a spray can in combination with such a supply apparatus with which the maintenance medium is supplied at the same time to a reduced number of the connection parts present, preferably in each case two connection parts. In comparison with the maintenance apparatus in accordance with claim 1, with this configuration the maintenance time is reduced.
With both configurations in accordance with the invention, individual steps of the maintenance procedure are automatically controlled, in particular after issue of a start signal, so that the maintenance apparatus works independently and after a maintenance procedure the handpiece or handpieces need only be removed.
The subclaims contain features which improve and intensify the maintenance and also the cleaning of the at least one handpiece and further lead to simple and compact constructions, reliable functioning and longer life time, and which can be economically manufactured.